Motorists have been urged to prepare for potentially hazardous conditions as snow is forecast across the South Island heading into the weekend.

The New Zealand Transport Agency said drivers should plan ahead and be ready for delays, with heavy snow warnings and watches issued by MetService.

Snow is expected down to 300 metres in Central Otago and parts of Canterbury from the Rangitata River south, with possible damage to trees and powerlines and significant travel disruption.

Queenstown Lakes could see snow to 400 metres, and snow is expected on the Dunedin to Waitati Highway (State Highway 1) from around 10am Friday.

Further north, snow is also possible to 400 metres in Canterbury and southern Marlborough, with mountain passes across the island likely to be affected.

Transport Agency system manager Mark Pinner said, “We got off relatively lightly with the snow so far this week. The highway closures we had in the MacKenzie Country were only short-lived and the impact was not widespread.”

“If you are heading away for the weekend, and especially if you are travelling on highways at higher elevations, make sure you are prepared and plan ahead using our Journey Planner.”

In the Westland District, motorists have also been warned of potentially severe southeast gale force winds from Friday afternoon.